Preparation of canned products



June 9, 1953 E N. HIGGINS ET AL 2,641,176

PREPARATION oF CANNED PRODUCTS Cam W4 mv atri/mmf 517m v INVENTORS A dwardjV. Higgins Vfnonf Evans @Hmmm-l' June 9, 1953 Filed June 21, 1945 E. N. HIGGINS ET AL PREPARATION OF CANNED PRODUCTS 2 Sheets-Sheet 2 Patented June 9, 1953 sirenas. e

.rance of'.Pennsylvania-fl Application June 21') 1945,Sria3l1l`oh60ll690i;

ZilCIamszi (Cl. 994-3621 l This i invention" relates td'the' sterilization of canned' foods "andclike'products `"and: is :fnanapv paratus and method lay-Whichy this" operation" may" be continuously" performed 2and coordi-i hated relationWith'afcan closingandl a labelingr f' machines. y

Mani/canned `foods-'arefcl'i'arged intoaftin cair4 inacooke'dor "semicookedf or even" raw" condi# ti'on, the vrcaxr sealed', and then the lcan` is `hea-ted forarprolonged periodici-time atxfa-temperature;l i*

usually-abovefthe iooili'ng jtemperature of "212 FV C'ommercially; this 4`is accomplished 'bywhargin'g batches of ffilled' closed"ca^ns"`into l'an autoclave; sealingthe.autoclave, admitting steam to'rnaina tainthezright. temperature.: after which they are held atsterili'zing temperature for the` necessary periodm time.. Then vthe..,autoclave must ,be cooled'until"`atmospheric pressure Within it' is reached, after-Which iseoperied.` Much time is lostdinf'this operation, andvit is necessaryitorf?" have severalriautoclaves to 1secure satisfactory continuity@ fof: operation.

Acoordinggto the present. invention, the :containers; after: being lledpare isealed. They then areracarriedaat a predeterminedcrate through:Y a bath; ofelliquid having a boilingfpoint substanti'aliyv higher:` than that of watert.. A minerali-.cil havingga iiash .point of around-.300 Fjxfor-:exe ampezmaybe used, such an ,oil .havingian even higher. boiling point. Thecontainers moveslovw ly@ but lscontinuously, through .':thisf-b ath forfthe necessaryfperiod of. time.

Moreover,accordinggto :ounnvention the` cans maymove rlirectlyromthe .closingimachine-into thesteriliz`ing Vbath. Fromi'ifthiszibath them/pass under .a hot Water spray Whichfrenioves the :high boilihgspoint iuid.. This fluid `:.according-l tofzour iriventionis recovered for refuser.. The cans then passrin-.zsuccessionpastdetergent;fcoolingaandsair drying spraysfdirectf-tto.awlabelingfrmachine so that the entire process canl proceed Without interruption.

machineof anyknown'fon preferredtype Ain-Which,l tlmaxca-ns` are :sr-iccessi-vely filled: andisealed. From.: this. machinefthe filled :and closed .cansare trans'- erifediftoacconveyor'belt 2.-'at'one endof` along... narrowetrough 3 ,f byza .transfer mechanism; as forr exampleca tpusher'f bar, not -shown The zbelt. slopesfzdown' into .the Itroughas i indicatedl at i4.. i In; the trough -isavbody of liquid f i5 that `has a.. boilingv p oirrl',v f substantially ihigher 1 thanr that oli! waters'. As fpreviouslyindicated; a liquid-1 having zv a-thcilin-O` point offatfleast; 250'- F.; and preferably, aimineral oil, having.afviash point` oilat. least.: 300 F. and an even higher boiling pointsishusedr. andtthe. temperaturefofctheebath. .-is.l kept isome- Tlieiconveycre. Whichtmammove ,.along.,tracks 6 mnizthe fside `Walls.above the bottom .andfwhich mayfsbeormedcof.' a-fsuccessionlof mesh .pa:r1'els",.v carriesftheicansaatolevellwhere .theyare entirely., submerged.: Ini'the trough..belowVY the conveyors aree steam-V :pipes-cf? to-.whichlhgh- ,temperatures high: `pressure f steam isa-supplied Additionally.. there-,are low: pressure -steam ypipes 1 ci .which'mays have"esmalllperforatiohs .therein so that a limited:

` f amount'ioficsteamxat lowerpressurermay fbedis.Y

chargedfinto the path.`4 The-steam pipes-Jafithus serves-thefipurposeafof. :more irapidly heatingthe li'quidsand :.cconstantly. agitatingsthev bath to#` ternperature;A

Atthe 'opposite-end ofi thetroughfthetconveyor slopes'-#upwardly ffatx to the :atop vof` the htrough. f. Beyondathe adisch'arge. endaofithetrough .the 'conveyor passes -overflanotiier-zvessel-:.19 alcove-whichV are hotr-Water spray nozzl'es.-cr pipes -i-l Gaf These spray fhot `vvate'ronto the cans, Washing ofi;A prac-3V tically "alladhereing oili lfrfcrnttherbathf THe-hot Water is collected finitheevessell -9 :vs/herenv hot Water and oil may be carried ofi to a separat/.ew ing fmeans. The' fwater: land i .ioil ntakenefronr: the vessel@ 'maycdischiargeg for fexaznpleiinto giacconi-1' tituoiis liuidliduidicentriiuge.'3I In .thef'cili disah charged into vessel lla from Which it is forced by a pump l2 directly to the sterilizing bath, or as shown, to a reservoir i3. The hot Water may, if desired, be reused. Beyond the Vessel 9 the conveyor passes over another vessel I5 above which are arranged sprays I6 for spraying the cans with hot Water and .a detergent such as soap. This Water is collected in the vessel l5 and may be recrculated. This operation removes the last vestige of oil from the cans. The conveyor also extends over another vessel l1 with sprays i8 above it for directing jets of cold water ontoI the cans to substantially cool the cans, the cold water being collected in the vessel Il for re-use. Next the conveyor extends past a drying station where a plurality of jets or sprays I9 of air are directed against the cans for thoroughly drying them. Thereupon the conveyor discharges the cans to a labeling machine designated 20, which may be of any known or preferred construction, and which accepts the cans as fast as they are delivered to it, applying the labels thereto and discharging them in condition to be packed. A converging disk conveyor (not shown), may satisfactorily transfer the cans from the main oonveyor to the labeling machine.

The trough is long enough and the liquid therein is maintained at a sufliciently high temperature to assure yadequate sterilization of the contents of the can, the speed of the conveyor also` being adjusted to give -proper sterilization. In order to correlate these factors, the drawings illustrate a variable speed control such as a rheostat 2| for variably controlling the speed of the closing machine, rheostat 22 for adjusting the speed of the main conveyor, and rheostat or other speed control means 23 for controlling the speed of the labeling machine. 24 indicates a thermostatic control element for the high pressure steam inlet pipe so as to adjust the temperature to the time of travel of the cans through the bath and maintain a uniform high temperature in the bath, there being a thermostatically controlled valve at 24a.

It will thus be seen that our invention enables the closing, sterilizing, and labeling of the cans to progress continuously and at a predetermined rate, each unit being correlated to each other so as to avoid work stoppage which result with the intermittent processes now required through the use of pressure cookers. It has been found that the cans successfully resist the pressure generated in them in passing through the hot oil bath, and cans which are defective can frequently visibly be detected, whereas present methods of pressure cooking afford no such opportunitiy for inspection. By reason of the hot water spray following the removal of the cans from the hot oil bath, practically all of the oil that is carried out by the cans is removed and recovered for re-use. Any slight film that remains is effectively removed by the detergent spray while the cooling jets accelerate the cooling of the cans to a temperature where they can be safely handled and drying currents of air conditionv the cans for immediate application of the labels.

As illustrated in the drawings, an exhaust hood 25 may be placed over the trough, to exhaust fumes or vapors therefrom, and another hood 26 may be over the several sprays. These discharge fumes and vapors at some remote or outside space.

While we have illustrated more or less schematically one specific embodiment of our invention, it will be understood that this is by way of illustration, and that various changes and modlfications may be made in the construction and arrangement oi the parts within the contemplation of our invention and under the scope of the following claims.

We claim:

1. Apparatus for continuously sterilizing sealed cans of food or the like, comprising a trough, a bath of mineral oil in said trough having a boiling point at atmospheric pressure substantially higher than the boiling point of Water, a conveyor extending into and out of and along the trough below the top of the trough so that cans on the conveyor will be submerged in the bath, high pressure steam pipes immersed in the liquid in the trough for' heating the liqiud, and low pressure steam pipes in the liquid having holesr therein for the escape of steam into the bath for agitating the bath and directly heating the liquid.

2. Apparatus for sterilizing closed food oontainers comprising an elongated trough, a conveyor movable along the trough below the top thereof and entering the trough at one end and emerging therefrom at the other, a bath of mineral oil in the trough, means for heating the oil p to a sterilizing temperature above 212 F., said means comprising a high pressure steam coil sub,- merged in the bath -below the conveyor, and a low pressure perforated steam pipe in the bath below the conveyor for directly heating and agitating the oil, the depth of the bath above the con. veyor being such as to cover containers on the conveyor.

EDWARD N. HIGGINS.-

VERNON P. EVANS.

References Cited in the le 0f this patent UNITED STATES PATENTS Number Name Date 633,066 Brewer Sept. 12, 1899 654,712 Arruti July 31, 1900 669,250 Birkholz Mar. 5, 1901 749,547 Fesenmeier Jan. 12, 1904 1,226,726 Volz May 22, 1917- 1,311,643 Fischer July 29, 1919 1,377,088 Martin May 3, 1921." 1,404,456 Martin Jan. 24, 1922 1,621,620 Bast Mar. 22, 1927 1,780,772 Washburne Nov. 4, 1930 1,923,421 Chapman Aug. 22, 1933 1,933,557 Kalvin Nov. 7, 1933 1,977,044 Christie et al. Oct. 16, 1934 1,983,805 Munson Dec. 11, 1934 2,124,010 Smith et al July 19, 1938 2,203,141 Gruetter June 4, 1940 2,282,187 Herlold et al. May 5, 1942 2,331,467 Griith et al Oct. 12, 1943 2,341,498 Bell Feb. 8, 1944 OTHER REFERENCES K. S. Markley and W. H. Goss, Soybean Chemistry and Technology, Chemical Publishing Co., 1944, pages 226 to 228. 

